Determine how much flexible PVC pipe you'll need. A quick and simple way to do this is to wrap the PVC pipe around from connection point to connection point and then mark on the pipe where it will fit onto each point. Add a couple inches to either end just to make sure you do not cut it too short. You can always trim excess length later.
Place the pipe in the jaws of the pipe cutter -- or secure the pipe down in a vise if you are using a hacksaw.
Cut through the pipe. If you are using a pipe cutter, simply squeeze the jaws closed. If using a hacksaw, saw all the way through the pipe and do not try to break the pipe off before the saw has gone straight through.